1. Field of the Invention
The present invention relates to fluid analysers and in particular it relates to improved forms of fluid analysers capable of determining the composition of the fluid, particularly the chemical composition. In particular the invention relates to analysers which are simple to operate and are both qualitative and quantitative in identification of the components within individual and/or a multitude of fluids. The invention enables analysis to a high degree of accuracy without having to change or put additional fluid analyser sensors into the system.
2. Discussion of the Background Art
Most analysers rely upon sensors gathering information from within frictional flow rates of fluids. However, the analyser of the present invention works by collecting the fluid sample via a non-invasive methodology and thus avoids contamination of the fluid to be analysed. In a preferred embodiment the invention relates to a fluid analyser that is portable and may be used to analyse the samples taken at a remote location and to interact with other fluid analyser systems usually of the same manufacture. This permits use of the analyser in a wide variety of environments and settings.
For the purpose of this document, Fluid means:                i) Consisting of any particles that move freely among themselves;        ii) “particle” means, a minute portion of matter;        iii) “matter” means, any of numerous subatomic and/or atomic constituents of the physical world that interact with each other;        iv) “constituents” means, anything that occupies a space.        
Portable fluid analysers are known and the breathalyser used to detect alcohol in a motorist's breath is an example of a portable fluid analyser. Portable, or mobile, analysers are also used for environmental purposes such as the determination of air purity around petrochemical complexes, gas fires and boilers. Portable or mobile analysers are also used in mining and in other hazardous activities to detect the presence of dangerous fluids.
Existing portable fluid analysers consist of a sampler and an analyser. They do however, suffer from certain disadvantages. Firstly the fluid sampler and the analyser make up a unitary apparatus with operators manning and being required to understand the complexities of the analyser. Furthermore, the results of the analysis cannot usually be compared on the spot with previous data because the previous data is generally stored in a remote location. An additional disadvantage is that typically portable analysers can usually detect no more than 4 gases in a fluid sample at any one time and specialty analysers can usually detect no more than 6 at any one time. The traditional analysers are further limited in that when working on gaseous mixtures they cannot detect a concentration above and/or below a saturation limit which depends upon the nature of the gas.
Existing fluid analysers tend to detect fluids in a flow of fluid in a stream as it passes a detection probe or probes. This technique suffers from the drawback that the probe must be cleaned after each analysis before any subsequent use and it is difficult to get the probe sufficiently clean to prevent contamination for the next test. Also it is sometimes necessary to recalibrate the probes between each analysis. In many existing fluid analysers each fluid is detected by means of an electro chemical sensor and the user needs to replace the sensor according to the fluid to be detected. It is then necessary to recalibrate the sensor to detect another fluid.
If the flow rate in one analyser is greater than that of another and the sensors are the same. The device with the greater frictional flow rate will normally provide a more accurate reading. However to obtain an even greater accuracy and a wider range of fluid analysis, a radioactive scan in a predetermined environment has been proposed to provide greater accuracy and quantity analysis report.
Chemiluminescence is sometimes used for gas analysis and involves the capturing and interpretation of emitted light during a chemical reaction. Absorption and desorption rates of molecules on surfaces of fluids and their transfer rates from a surface of a fluid are dependent upon temperature. This action is termed surface diffusion and where there is an equilibrium both absorption and desorption occur creating corresponding fluxes of equal magnitude. This type of analyser suffers from the disadvantage that it relies on thermal or chemical reactions induced or otherwise to analyse the intensity values of fluids and thus determine the amounts of fluids that are present.
Gas Chromatography is also used for fluid analysis. This technique separates a mixture of fluids by passing it in solution or suspension through a medium in which the components move at different rates to enable identification of the different components present in the mixture. The fluid analyser system of the present invention however, has no need to pass the sample in the container through a mixture or suspend it in a liquid in order to assess the identity of the contents or their volume within the sample.
It has also been proposed that fluids may be analysed from the reconstructed gas/fluid emissions formed and identified by the addition of chemicals in a calculated manner. The surface relaxation of fluids has the causal effect of emitting a variable light. The variable light from the chemical reaction helps create the environment where electrons invade the x, y and z axis through a process of spilling. Friedel oscillations are created near the surface of fluids which may or may not screen the ions. Where the ions are allowed to withdraw back into the surface of a material the energy received from the material will be reduced or changed. The changes can be used to indicate the nature of the components of the fluid; this process however suffers from the disadvantage that it relies on a chemical reaction.
The refractive index is used to differentiate the light reflected back from different substances thereby providing an identity; however, the light cannot be clearly identified much beyond 6 decimal places which have the disadvantage of categorising different substances under the same refractive index number.
Mass Spectrometry can also be used. The objective of the Mass spectrometry is to separate each mass from the next integer mass and this can be achieved in several ways the first of which is via Unit resolution mass 50 distinguishable from mass 51, for example. The magnetic sector using the Gaussian Triangle peak method of differentiation. The Fourier Transform Ion Cyclotron Resonance (FTICR) system utilises twin peaks with a Lorentzian shape and 10% valley resolution. The Time of Flight (TOF) mass spectrometer is resolved to a 50% peak-height definition incorporating the Gaussian triangle shape. The two peaks are resolved to a 50% valley.
Mass Spectrometry is concerned with the separation of matter according to atomic and molecular mass. It is most often used in the analysis of organic compounds of molecular mass up to as high as 200,000 Daltons, (Atomic Mass Unit) and until recent years was largely restricted to relatively volatile compounds. Continuous development and improvement of instrumentation and techniques have made mass spectrometry the most versatile, sensitive and widely used analytical method available today. However, the fluid analyser system of the present invention is capable of a definition of a fluid particle beyond that of a mass spectrometer. Furthermore, the analysis of the present invention utilises captured sample/s where integrity of the sample is maintained. Mass Spectrometry also suffers from the difficulty that integrity is problematic.
In Mass Spectrometry radiation sources, such as lasers, are used, the wavelength of current lasers occurs in approximately the visible wavelengths. Conversion of visible wavelengths into shorter wavelength radiation has many practical applications beyond the intrinsic theoretical interest in production mechanisms, as absorption sources, x-ray heating sources, x-ray lasers. Radiation is amplified through laser energy aimed at the sample. The fluid analyser of the present invention does not require additional energy radiation in order to amplify the signal radiative source of the fluid in the sample container to facilitate the identity of the fluid.
U.S. Pat. No. 6,271,522 suggests that spectrometry may be used for gas detection. Similarly U.S. Pat. No. 5,319,199 uses infrared and ultra violet radiation to detect the gases present in vehicle emissions. U.S. Pat. No. 4,746,218 is concerned with spectral absorption to detect and analyse gases. None of those devices enable the simultaneous detection and analysis of a multitude of gases and none of them can detect gases at a low enough concentration to be useful in, for example, comprehensive medical diagnosis.
Our published PCT Application WO 03/044503 relates to a fluid analyser system, in particular a portable fluid analyser system which overcomes the various disadvantages previously described. The analyser of PCT publication WO 03/044503 does not require probes in the fluid to be analysed and operates on a self contained static fluid sample which thus minimises or avoids contamination of the sample. The analyser of PCT Publication WO 03/044503 has the additional benefit that the sample once taken remains sealed to prevent contamination and that the sample can be stirred.